tty: Fix the digi acceleport driver NULL checks

This now refcounts but doesn't actually check the reference was obtained in
all the places it should.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/usb/serial/digi_acceleport.c b/drivers/usb/serial/digi_acceleport.c
index fd35f73..b92070c 100644 (file)
--- a/drivers/usb/serial/digi_acceleport.c
+++ b/drivers/usb/serial/digi_acceleport.c
@@ -609,8 +609,10 @@ static void digi_wakeup_write_lock(struct work_struct *work)
 static void digi_wakeup_write(struct usb_serial_port *port)
 {
        struct tty_struct *tty = tty_port_tty_get(&port->port);
-       tty_wakeup(tty);
-       tty_kref_put(tty);
+       if (tty) {
+               tty_wakeup(tty);
+               tty_kref_put(tty);
+       }
 }
 
 
@@ -1682,7 +1684,7 @@ static int digi_read_inb_callback(struct urb *urb)
                priv->dp_throttle_restart = 1;
 
        /* receive data */
-       if (opcode == DIGI_CMD_RECEIVE_DATA) {
+       if (tty && opcode == DIGI_CMD_RECEIVE_DATA) {
                /* get flag from port_status */
                flag = 0;
 
@@ -1763,10 +1765,12 @@ static int digi_read_oob_callback(struct urb *urb)
                        return -1;
 
                tty = tty_port_tty_get(&port->port);
+
                rts = 0;
-               rts = tty->termios->c_cflag & CRTSCTS;
+               if (tty)
+                       rts = tty->termios->c_cflag & CRTSCTS;
                
-               if (opcode == DIGI_CMD_READ_INPUT_SIGNALS) {
+               if (tty && opcode == DIGI_CMD_READ_INPUT_SIGNALS) {
                        spin_lock(&priv->dp_port_lock);
                        /* convert from digi flags to termiox flags */
                        if (val & DIGI_READ_INPUT_SIGNALS_CTS) {